We start by: 

(1)	downloading the CRSP universe of stock for each of the following samples, which will then be used to populate the market-model Eventus-produced cumulative abnormal returns in 12 samples that correspond to the 12 states that adopt poison pill statutes  (MN, SC, WA, MD, MO, MI, ME, CT, TX, MS, VT and WY):

1.	CRSP list of Permno-s as of 01/03/1994 (Monday) (used for MN sample)
2.	CRSP list of Permno-s as of 01/03/1997 (Friday) (used for SC and WA samples)
3.	CRSP list of Permno-s as of 01/02/1998 (Friday) (used for MD and MO samples)
4.	CRSP list of Permno-s as of 01/03/2000 (Monday) (used for MI sample)
5.	CRSP list of Permno-s as of 01/03/2001 (Wednesday) (used for ME sample)
6.	CRSP list of Permno-s as of 01/03/2002 (Thursday) (used for CT and TX samples)
7.	CRSP list of Permno-s as of 01/02/2004 (Friday) (used for MS sample)
8.	CRSP list of Permno-s as of 01/03/2007 (Wednesday) (used for VT sample)
9.	CRSP list of Permno-s as of 01/03/2008 (Thursday) (used for WY sample)

(2)	For those samples of stocks, per each state passing a poison pill statute, we create a list of PERMNO & event date that we submit through WRDS Eventus facility to calculate market-model-based (using equally-weighted market returns) cumulative abnormal returns for six event windows (-3 to +3, -2 to +2, -1 to +1, -1 to 0, 0 to 0, and 0 to +1) using the following event dates, as obtained by the poison pill statutes per each state, retrieved via Hanes Online courtesy of Michael Wittry:

1.	For state of MN - signed by governor 5/5/1995
2.	For state of SC - approved by governor 6/8/1998 
3.	For state of WA - approved by governor 3/23/1998
4.	For state of MD - approved by governor 5/13/1999
5.	For state of MO - approved by governor 7/13/1999
6.	For state of MI - approved by governor 7/23/2001
7.	For state of ME - effective 7/1/2001 (imputed approval date is 90 days before, so 4/2/2001, a Monday)
8.	For state of CT - approved by governor 6/26/2003
9.	For state of TX - approved by governor 5/29/2003
10.	For state of MS - approved by governor 4/20/2005
11.	For state of VT - approved by governor 6/5/2008
12.	For state of WY - approved by governor 3/3/2009

(3)	We then combine the files with CAR returns for each of the twelve cohorts above. 
(4)	We use the main analysis file “PPL_toanalyze” and keep the first observation per firm in states with poison pill statutes, for the period 1994-2009. 
(5)	We then merge into the file from (3) the file from (4). In the resulting file we set PPL (i.e., poison pill statutes indicator) as zero if missing.
(6)	We then winsorize the six CAR returns at 1% in each tail and run the regression: Winsorized CAR = PPL and SIC-3 (three digit SIC industry) fixed effects. Results are shown in Table OA 10.
